Manila clam

The latest assessment of French aquaculture was conducted in 2017, while the latest assessment of Italian aquaculture was conducted in 2022.

The Manila clam is farmed in France and Italy using both wild-collected seed and hatchery-produced seed. Farming requires little energy, and no feed or fertiliser is used.

Manila clams are filter feeders and feed on naturally occurring plankton. As a result, they produce virtually no waste. The environmental impact is generally limited, although farming areas may affect ecologically valuable habitats. No chemical treatments are used. Diseases may occur, but the risk of transmission to wild populations is considered low. CO₂ emissions are low.

Management of aquaculture in France and Italy is generally largely effective. There is no AIP for this aquaculture, and only one company is certified by Friend of the Sea. No ASC certification is available.

The stock of Manila clams in the Gulf of Morbihan (ICES VIIIa) is insufficiently monitored to properly assess its current status. The species has a low sensitivity to fishing pressure, but the latest available data indicate low recruitment of young clams.

Hand gathering of Manila clams is highly selective and results in virtually no bycatch. Discards are negligible. The impact on the ecosystem and seabed is limited. CO₂ emissions are virtually zero, and there is no risk of lost fishing gear.

Management was well organised until 2019, but recent data are lacking. As a result, it is difficult to assess how effective current management is. There is no FIP, and the fishery is not MSC-certified.

Little is known about the stock of Manila clams in China. There are no reliable stock data or official assessments available. The species grows quickly, but it is likely to be subject to excessive fishing pressure in this area.

Dredge fisheries for Manila clams have a major impact on the seabed and benthic life. The level of bycatch is unknown, and discards are likely to be high. Damage to protected species appears to be limited, but cannot be ruled out.

Management is insufficient. There are general fisheries regulations, but enforcement is inadequate and little is known about the effectiveness of measures to protect nature, habitats and reduce bycatch. Several fisheries participate in a FIP, but the fishery is not MSC-certified.